Relevant prior art is disclosed in U.S. Pat. Nos. 3,506,433; 3,223,517; and 2,603,560.
In various plants, such as, for example, tobacco, tomato, cotton, soybean plants, etc., undesirable secondary growth, which is generally referred to as "suckers", creates a serious problem because the suckers develop rapidly to shade desired portions of the plant, compete for the nutrients, and tend to ruin the quality of such desired portions. In the tobacco plant, secondary buds form at the points where the leaf stems join the plant, and later after the flower is removed grow rapidly to form sucker growths extending over the leaves. The sucker growths can be removed manually, but this is a laborious and expensive proceeding. The use of sucker oil and chemicals, while effective in control of such secondary growth, nevertheless have in the past had serious disadvantages. The sucker oil tends to form leaf and stalk damage, causing soft spots that are attacked by microbes, and also there is a lack of control of the lower sucker stalks. The chemicals which have previously been used produce cellular changes in the leaf tending to reduce the filling capacity of the treated tobacco for cigarette manufacture. Further, the cost of the chemicals has been high.